The goal of this project is to contribute to the understanding of the neural basis for and relationship between memory and language, by investigating the acquisition and use of "common ground" in communication. The experimental approach uses the lesion method to interrelate neuropsychological and neuroanatomical findings, using both group studies and multiple single-case studies of neurological patients with focal brain lesions. The proposed work builds on an exciting finding from my doctoral work: severely amnesic patients can acquire common ground (shared referential labels used to facilitate rapid and efficient communication) in regular interactions with familiar partners. The crucial cognitive components and neuroanatomical correlates of this learning, however, have yet to be determined. One principle aim here is to define and characterize those cognitive and neural mechanisms supporting common ground in communication. The nature of the task used in my experimental work involves "real-world" learning and communication. The fact that individuals with amnesia performed so well in this truly real-world type of collaborative interaction is very exciting with respect to rehabilitation possibilities. The second aim of this work is to test the clinical efficacy of this paradigm by designing and implementing a collection of single case intervention studies using the collaborative referencing task in patients with circumscribed impairments of learning and memory, aimed at improving their daily functioning. [unreadable] [unreadable] [unreadable]